The known videoconferencing equipments comprise, in each specified site, picture capture means such as a video camera and sound capture means such as a microphone, which respectively allow the acquisition of the image and the acquisition of the sound of the voice of a local user. Moreover, they also comprise image restitution means, such as a video projector cooperating with a projection screen, and sound restitution means, such as loudspeakers, which respectively allow the restitution of the image and the restitution of the sound produced by a distant user.
All these means are customarily situated in a scheduled room equipped for this purpose, the so-called videoconferencing room or studio, which is generally locked outside of conferences in order in particular to prevent the theft of the hardware. A videoconference would therefore be organized in advance, and presupposes a scheduled appointment between the users who are summoned to assemble in the videoconferencing studio at a precise date and precise time, the conference having a precise aim, generally professional. Videoconferences constitute formal meetings. In each site, the users sit down in front of a table, the screen being arranged vertically on the other side of the table. They behave as if they were seated at a meeting table, and as if the distant users were seated facing them, on the other side of the table.
All these constraints make the videoconferencing service rather user-unfriendly since it is adapted to so-called “formal” communication only. In fact, this service is still largely reserved for the professional domain, that is for the business world. Certainly, solutions have been proposed to improve the copresence effect afforded by videoconferencing systems. For example, in the document FR-A-2 761 562, means of spatially distributing the sound are proposed so as to establish a correspondence between the sound generated by each distant participant and his image displayed on the screen of a relevant site. Nevertheless, for the reasons indicated hereinabove, videoconferencing systems have not yet become the instruments of remote user-friendliness that might have been expected.